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Atrazine (ATZ) is one of the most used active principles in agricultural systems. This pesticide has the ability to easily accumulate in terrestrial and aquatic environments, causing impacts with chronic adverse effects. Avoidance tests are tests that seek to assess the concentration from which a given organism escapes, that is, migrates to another habitat. They are being used as a modality of innovative and minimally invasive ecotoxicological tests. Our objective was to evaluate the sensitivity and possible toxic effects of ATZ in bullfrog tadpoles (Lithobates catesbeianus), through avoidance tests and oxidative stress analyses. We performed the behavioral avoidance test lasting 12 h, with observations every 60 min in a linear multi-compartment system with seven compartments. Each compartment corresponded to a concentration: negative control, 1, 2, 20, 200, 2000, 20,000 µg L−1. After the selection of habitat, organisms were forcedly maintained in the chosen concentrations for 48 h and then, metabolic effects were measured assessing the blood plasma amino acid profile and liver protein degradation. We also determined the effective concentrations of ATZ tested at 0 h and 48 h. The results showed that there was an effect of the treatment on the distribution of tadpoles, but not on the hours or on the combined effect (interaction). The biochemical analyses also showed a concentration-dependent relationship which caused significant toxic effects even in a short period of time. In conclusion, these frogs were able to avoid places with high concentrations of ATZ in the first hours of exposure, which suggests that in the natural environment these animals can migrate or avoid areas contaminated by this herbicide; however, depending on the selected concentration, serious biochemical consequences can occur.

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Combining simultaneously lung and liver procurement in controlled donation after circulatory death (cDCD) using normothermic abdominal perfusion (NRP) for abdominal grafts and cooling and rapid recovery technique (RR) for the lungs increases the complexity of the procurement procedure and might injure the grafts. A total of 19 cDCDs from two centers using this combined procedure were evaluated, and 16 liver and 21 lung transplantations were performed. As controls, 34 donors after brain death (DBDs) were included (29 liver and 41 lung transplantations were performed). Two cDCD liver recipients developed primary nonfunction (12.5%). No cases of ischemic cholangiopathy were observed among cDCD recipients. The 1‐year and 2‐year liver recipients survival was 87.5% and 87.5% for the cDCD group, and 96% and 84.5% for the DBD group, respectively (P = .496). The 1‐year and 2‐year lung recipients survival was 84% and 84% for the cDCD group and 90% and 90% for the DBD group, respectively (P = .577). This is the largest experience ever reported in cDCD with the use of NRP combined with RR of the lungs. This combined method offers an outstanding recovery rate and liver and lung recipients survival comparable with those transplanted with DBDs. Further studies are needed to confirm our findings.  相似文献   
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Traditional criteria used in selecting wound care interventions are being slowly replaced with an evidence-based practice approach. The value of such an approach for providing optimal care has been established, but the definition of evidence-based care and the process used to generate evidence continue to evolve. For example, the role of studies developed to demonstrate efficacy, randomized controlled trials, the value of effectiveness studies designed to evaluate outcomes in real world practice, and the use of disease-oriented (interim) study outcomes for wound care research, such as reduces wound fluid or improves granulation tissue formation, have been topics of international conversations and consensus documents. In addition, the use in some clinical studies and most systematic study reviews of ingredient or characteristic-based categories to group products that may not share a common operational definition of how they function has led to a high variability in outcomes, resulting in inconclusive or low-level evidence. These concerns and debates, along with their influence on practice, may cast doubt on the value of evidence-based practice guidelines for some clinicians, slowing their rate of implementation, and extending the discussion about definitions of evidence-based care and the relative merits of various research designs. At the same time, amid growing concerns about medical device safety, clinicians must answer 3 questions about an intervention and its related products or devices in order to provide safe and effective care: (1) Can it work? (2) Does it work? (3) Is it worth it? Reviewing current knowledge about wound care, wound treatment modalities, and the basic principles of research within the existing framework of questions to be answered suggests a clear path toward obtaining much-needed evidence. In wound care, using clearly defined processes to study patient-centered outcomes (eg, quality of life, complete healing) and only product groupings that meet an operational definition of functioning (eg, moisture-retentive) will help clinicians decide whether an intervention can work and does work and whether the value of the clinical and economic benefits is greater than the potential harm and cost.  相似文献   
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Study ObjectiveTo assess the efficacy of Tissucol Duo (Baxter AG, Vienna, Austria) fibrin sealant in decreasing the incidence of lymphocele (LC) after pelvic laparoscopic lymph node dissection using harmonic shears.DesignRandomized controlled trial (Canadian Task Force classification level I).SettingTertiary referral and educational center.PatientsSeventy-four patients randomized to the use of sealant per hemipelvis.InterventionFibrin sealant.Measurements and Main ResultsAfter bilateral pelvic lymphadenectomy a fibrin sealant was used in 1 hemipelvis but not the other, applied in 41 patients (55.4%) to the left and 33 patients (44.6%) to the right hemipelvis. The primary outcome was the incidence of LC after surgery in symptomatic and asymptomatic patients. Imaging (ultrasound, computed tomography, and magnetic resonance) was performed to detect LC at 3, 6, and 12 months after surgery. Overall, 26 patients (35.1%) developed LC, and 4 were symptomatic (5.4%). Allowing patients to serve as their own treatment group and control, the hemipelvis treated with Tissucol Duo corresponding to the treatment group and that not treated to the control group, LCs were found in 17 (23%) and 14 (19%) cases, respectively, but the difference was not significant. The mean initial LC maximum diameter was 27.1 mm (standard deviaiotn, 35.2), and LCs tended to decrease in size during the first year to a mean of 8.7 mm.ConclusionApplication of Tissucol Duo fibrin sealant after laparoscopic pelvic lymphadenectomy using ultrasonic shears does not decrease the occurrence of symptomatic or asymptomatic LC.  相似文献   
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